a squeel that loud would only be heard on a pig farm. is it a constant noise? is it louder or softer when you apply the brakes? could it be a lever rubbing on a shaft? what happens to it when you engage the blades?

the noise only happends when I squeeze the brake lever, it will go away when I release the lever, engaging the blades does not change the noise. It sounds like worn brake bands (metal on metal) But the machine is new with about 100 hours on it. Thank you for any help with this problem..